1613074-01-3Relevant academic research and scientific papers
Synthesis of Bridged Azacycles and Propellanes via Nitrene/Alkyne Cascades
May, Jeremy A.,Wang, Qinxuan
, p. 3039 - 3044 (2020)
A nitrene/alkyne cascade reaction terminating in C-H bond insertion to form functionalized bridged azacycles from carbonazidates is presented. Due to an initial Huisgen cyclization, all carbonazidates reacted with the alkyne in an exo mode in contrast to the use of sulfamate esters, which react predominately in an endo mode. Substrates with different ring sizes as well as different aryl and heteroaryl groups were also explored. Variation of the nitrene tether showed that 7-membered rings were the maximum ring size to be formed by nitrene attack on the alkyne. Examples incorporating stereocenters on the carbonazidate's tether induced diasteroselectivity in the formation of the bridged ring and two new stereocenters. Additionally, propellanes containing aminals, hemiaminals, and thioaminals formed from the bridged azacycles in the same reaction via an acid-promoted rearrangement.
Carbene cascades for the formation of bridged polycyclic rings
Jansone-Popova, Santa,Le, Phong Q.,May, Jeremy A.
supporting information, p. 4118 - 4127 (2014/06/09)
A general strategy to synthesize bridged polycyclic molecules is presented. The synthesis is accomplished via a cascade reaction initiated by rhodium carbene formation. Subsequent intramolecular reaction with an alkyne is then followed by a transannular C-H bond insertion. A rationale for prediction of the major structural isomer that is formed is described and applied to a wide variety of substrates. This rationale is based on conformational and stereoelectronic considerations for the ring system in the substrate.
